<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<div id="dv1"></div>
	</body>
	<script>
	var dv1=document.getElementById("dv1");
	// 定时操作
	// window.setInterval(function(){
	// 	dv1.innerHTML=new Date()
	// },1000)
	 window.setTimeout(function(){
		 dv1.innerHTML=new Date()
	 },3000)
	
	</script>
</html>
